Blast furnace structure

ABSTRACT

Refractory bricks above the cylindrical section are divided into some sections and the bricks in each section are supported by each ring girder which in turn is supported by the support disposed outside of the main body of the blast furnace.

United States Patent [1 1 Matsushima et a1.

[ 1 July 17, 1973 BLAST FURNACE STRUCTURE [75] inventors: MasatoshiMatsushima,Makot0 Nishinomiya, both of Yokohama, Japan [73] Assignee: Ishikawajima-Harima Jukogyo Kabushiki Kaisha, Tokyo-t0, Japan [22] Filed: Aug. 13, 1971 2] Appl. No.: 171,576

[30] Foreign Application Priority Data Nov. 11, 1970 Japan 45/99288 [52] US. Cl..' 266/25, 266/32, 266/43 [51] 1nt. Cl. F27b 1/12 [58] Field of Search 266/25, 32, 43

[56] References Cited UNITED STATES PATENTS 718,313 1/1908 Coffin 266/25 1,036,350 8/1912 Scott 266/32 FOREIGN PATENTS OR APPLICATIONS 280,043 3/1914 Germany ll 266/32 855,532 12/1960 Great Britain. v 266/25 1,039,082 9/1958 Germany i l i i 266/32 9/1907 France 266/25 Primary Examiner-Gerald A. Dost Attorney-Albert (I. Nolte, Albert Nollc,.|r. e1 ill.

[57] ABSTRACT Refractory bricks above the cylindrical section are di,- vided into some sections and the bricks'in each section are supported by each ring girder which in turn is supported by the support disposed outside of the main body of the blast furnace.

4 Claims, 5 Drau'ing Figures mgmmm 1 ma sum 1 or 4 poowoop FIG! INVENTORS MASATOSHI MATSUSHIMA MAK OTO NISHINOMIYA ATTORNEYS PAIENIEDJUL 1 1 ma SHEEI 2 BF 4 INVENTORS MASATOSHI MATSUSHIMA MAKOTO NISHINOMIYA BY 77,4; 9* m;

ATTORNEYS Pmmcm 3.746.327

' sum 3 er 4 j FIG3 INVENTORS MASATOSHI MATSUSHIMA MAKOTO NISHINOMIYA JBY 2 ATTORNEYS v PAIENIED JUL I 7 I973 SHEEI [IF 4 INVE N TORS MASATOSHI MA TS'USHIMA MAKOTO NISHINOM! YA A T TORNE YS BLAST FURNACE STRUCTURE The life of the blast furnaces is dependent upon the life of the bricks, that is how the life of the bricks may be improved.

The service life of the blast furnace is dependent upon how the service life of refractory bricks may be elongated, and the blast furnaces of the type illustrated in FIGS. 1 and 2 have defects in this sense.

There has been proposed a cooling system in which horizontal cooling plates are used, which also serve as the supports for refractory bricks. However, the horizontalcooling plates are also damaged and it is difficult to continuously insert the horizontal cooling plates. Therefore, it is impossible to elongate the service life of refractory bricks even when the horizontal cooling plates are employed.

In view of the above, it has been a great problem in the recent blast furnace construction how to protect the steel-plate shells in the short cylindrical section and below the shaft or how to increase the service life of refractory bricks in these portions.

The present invention contemplates to increase the service life of refractory bricks in the cylindrical section and below the shaft so as to improve the life of the furnace, and is characterized in that the portion above the cylindrical section of the furnace is divided into a plurality of steps by, ring girders in such a manner that the bricks in each of the divided steps may be supported by each of the ring girders which are joined to the steel-plate shells.

The invention will become more apparent from the following description of the preferred embodiment thereof taken in conjunction with the accompanying drawings.

FIGS. 1 and 2 are fragmentary front views partly in section of the conventional blast furnaces;

FIG. 3 is a fragmentary front view partly in section of a blast furnace structure in accordance with the present invention;

FIG. 4 is a fragmentary enlarged view thereof; and

FIG. 5 is a fragmentary enlarged view thereof illustrating the arrangement for externally cooling the steelplate shells in a blast furnace shown in FIG. 3.

There have been proposed various methods for improving the life of refractory bricks.

Concerning the problem how the service life of refractory bricks may be elongated, an example is shown in FIG. 1. A ring plate 0 is disposed to surround the steel-plate shell 0, and is supported by a support d. A

vertical cooling plate I; is disposed along the inner surface of the steel-plate shell. The weights of the steelplate shell a and the furnace top equipment (not shown) are supported by the support d and the load of refractory bricks a [aid from the bottom to the top of the shaft is supported by the foundation. Another example is illustrated in FIG. 2 in which a ring girder 3 supported by a support d is fixed to the cylindrical section f, so as to support the load of refractory bricks above the section f, by the ring girder g and the support d, and the load of the firebricks below the bosh f is supported by the foundation.

In the blast furnace of the type illustrated in FIG. 1, when the refractory bricks in the bosh f are damaged by the abrasion and chemical corrosion of the charge or is coming off from the furnace wall, the bricks in the cylindrical section f, and the shaft f, are also damaged or come off from the furnace wall. For example the bricks in the bosh f,, the cylindrical section f and the shaft f, are damaged and come off from the furnace wall even six months or twelve months after the starting the blast furnace operation. Therefore the life of the blast furnacebecomes very shorter. In the blast furnace of the type illustrated in FIG. 2, the service life may be improved because the bricks in the cylindrical section f, are supported by the ring girder 3, but the service life is about one and a half or two years because the refractory bricks e are damaged by the abrasion and chemical corrosion by the charge.

When the refractory bricks are damaged as described above, the vertical cooling plates placed inside the steel-plate shells are exposed to the high temperature furnace gases and the charge in the furnace so that they are damaged. When the cooling plates are damaged, the furnace must be cooled only from the exterior of the steel-plate shells, and the life of the blast furnace is remarkably reduced.

Between the bosh 2 and the short cylindrical section 3 is disposed a ring girder 6 to support the bricks 5 in the cylindrical section 3, and another ring girder 7 is disposed between the cylindrical section 3 and the shaft 4 to support the bricks 5 in the lower portion of the shaft 4. A further ring girder 8 is disposed to support the bricks in the portion of the shaft above its midportion. These ring girders 6, 7 and 8 are welded to the steel-plate shell 1 in such a manner that the steps are formed as shown in FIG. 3. The outer sides of the ring girders are supported by brackets 9, 10 and 11 respectively which in turn are securely fixed to a support 12.- Reference number 13 designates a vertical cooling plate disposed within the steel-plate shell 1.

The bricks in each small section above the cylindrical section 3 are supported by each of the ring girders 6, 7 and 8 respectively, and the load exerting on thering girders in turn are supported by the support 12 through the brackets 9, l0 and 11.

Even when the bricks Sin the bosh 2 are damaged by the abrasion and chemical corrosion by the charge or come off from the furnace wall, the bricks in the cylin drical section 3 and the shaft 4, the bricks 5 may be prevented from coming off from the furnace wall because these bricks 5 are supported by the ring girders 6, 7 and 8 in the manner described above. Therefore it may be next to impossible to protect the bricks 5 from the abrasion and chemical corrosion by the charge, but the service life may be remarkably increased. The cooling plate 13 may be prevented to be exposed and pregirder 8 on one hand and the steel-plate shell I and the ring girder 7 on the other hand so that the load of the bricks may be supported by the bracket 9. In this case, the brackets 10 and 11 may be eliminated.

In another modification illustrated in FIG. 5, sprinkler pipes 15 are disposed outwardly of the steel-plate shells l and below the ring girders 6, 7 and 8 respectively in order to protect the steel-plate shells 1 when the cooling plate 13 should fail. Furthermore, a water collection plate or ring 16 is formed along the outer periphery of each of the ring girders 6, 7 and 8 so as to define a water conduit. Therefore, the welds between the ring girders 6, 7 and 8 and the steel-plate shells l and the steel-plate shells 1 are sufficiently cooled so that the steel-plate shells 1 may be prevented from being cracked at the welds. In addition, various variations and modifications may be-effected within the scope of the present invention.

As described above, the refractory bricks above the cylindrical section 3 are divided into some sections and the bricks in each section aresupported by each ring girder which in turn is supported by the support disposed outside of the main body of the blast furnace. Therefore the present invention has the following advantages:

I. that even when the bricks in the bosh are somewhat damaged by the abrasion and chemical corrosion by the charge, the bricks in the cylindrical section may be prevented from coming off from the furnace wall so that the service life of the bricks above the cylindrical section may be much improved;

ll. that the ring girders of the present invention are different from the supports for bricks which are welded to the inner surface of the steel-plate shell in that the ring girders are very reliable in function and will last as long as the blast furnace does;

"I. that even when the bricks are damaged or come off, the self-lining by the charge may be effected because .of the provision of the stepped portions so that the protective coating for the steel-plate shells and the cooling plates. are formed to minimize the damage to the cooling plate;

IV. that the provision of the shelves also serves to easily form thereliable protective layers which are formed by filling the amorphous refractory materials from the exterior of the steel-plate shells when the bricks are damaged; and

V. that even when the bricks are damaged, the high temperature gases in the blast furnace flow in the direction indicated by the arrows so that the cooling plates and the shells ,are locally heated and the abrasion or damage to the upper bricks and to the cooling plates may be prevented.

What is claimed is:

l. A blast furnace comprising a steel shell, refractory bricks lining said shell and defining bosh, cylinder and shaft zones of the furnace, a plurality of ring girders welded to said shell and projecting into said lining to define supporting surfaces for the bricks thereabove, the supporting surfaces of adjacent girders being at least partially vertically aligned, and support means for said girders externally of the furnace.

2. A blast furnace comprising a steel shell, refractory bricks lining said shell and defining bosh, cylinder and shaft zones of the furnace, a plurality of ring girders welded to said shell and projecting into said lining to define supporting surfaces for the lining. thereabove, the supporting surfaces of adjacent girders being at least partially horizontally overlapped, ,and support means for said girders externally of the furnace.

3. A blast furance as claimed in claim 2 wherein said support means comprises a substantially horizontal column and each girder is secured to said column-by a corresponding bracket. 3 v

4. A blast furnace as claimed in claim 2 wherein said support means comprises a substantially vertical column to which a lower one of said girders is secured by girders being sup- 

1. A blast furnace comprising a steel shell, refractory bricks lining said shell and defining bosh, cylinder and shaft zones of the furnace, a plurality of ring girders welded to said shell and projecting into said lining to define supporting surfaces for the bricks thereabove, the supporting surfaces of adjacent girders being at least partially vertically aligned, and support means for said girders externally of the furnace.
 2. A blast furnace comprising a steel shell, refractory bricks lining said shell and defining bosh, cylinder and shaft zones of the furnace, a plurality of ring girders welded to said shell and projecting into said lining to define supporting surfaces for the lining thereabove, the supporting surfaces of adjacent girders being at least partially horizontally overlapped, and support means for said girders externally of the furnace.
 3. A blast furance as claimed in claim 2 wherein said support means comprises a substantially horizontal column and each girder is secured to said column by a corresponding bracket.
 4. A blast furnace as claimed in claim 2 wherein said support means comprises a substantially vertical column to which a lower one of said girders is secured by a bracket, the upper ones of said girders being supported on said shell by ribs. 